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Updated: May 11, 2026

Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing
Published on: December 11, 2017
Utility of a new left ventricular asynchrony index as a predictor of reverse remodelling after cardiac
Maria Cristina Porciani1, Alessio Lilli, Roberto Macioce
1Department of Heart and Vessels, University of Florence, Viale Morgagni 85, Florence 50134, Italy. cporciani@hotmail.com
Aims:
The majority of tissue Doppler indexes proposed to predict left ventricular (LV) reverse remodelling in cardiac resynchronization therapy (CRT) reflects LV asynchrony as assessed in ejection phase. We evaluated the predictive value of a new strain-imaging parameter reflecting the total amount of time spent by 12 LV segments in contracting after aortic valve closure.
Methods And Results:
Fifty-nine patients who fulfilled current treatment recommendations were studied before and 6 months after CRT. Time to tissue Doppler systolic peak velocity (Ts) and time exceeding aortic closure (ExcT) in strain curves were measured in 12 LV segments. Ts standard deviation (Ts-SD) and sum of ExcT of overall 12 LV segments (oExcT) were analysed. After 6 months, responders were defined according to > or =15% LV end-systolic volume reduction. Responders (47%) when compared with non-responders (53%) had significantly higher baseline Ts-SD and oExcT values. Receiver operating characteristic (ROC) curve analysis demonstrated that an optimal cutoff value of 760 ms for oExcT yielded 93.5% sensitivity and 82.8% specificity. For Ts-SD at the cutoff of 32 ms, 82% sensitivity and 39% specificity were obtained. Area under ROC was significantly larger for oExcT than for Ts-SD.
Conclusion:
o-ExcT is able to predict LV reverse remodelling after CRT.

